This is why I never chronographed any of my hunting bows. Too many different readings from the different chrono's used.
I gauge how satisfied I am with my bows shooting arrows 9-10 gpp at 20 yds. When I release, and see how fast the arrow hits the mark...or how slow..will determine if the bow is a keeper for me.
When my Trad shop was open, I carried 7 lines of custom bows, we did a lot of shooting, testing and comparing. Never chronographing....the naked eye will tell you about your bows performance, especially out to the longer yardages. One bowyer told me his 55# bow would shoot a 540 grain arrow 193 fps.
We took the bow to the compound shop I use to work in, set up the chronograph and fired 5 arrows through. 540 grains...never exceeded 182 fps. That's 2 different machines, giving 2 different readings and quite sizable at that.